I just bought a couple new 9.6V batteries for my old Makita drill. I was always told that those particlular batteries should be run completely down before recharging. I know some newer batteries can be recharged at any stage of use. I’m wondering if I should still follow the advice to completely drain the Makitas.
Thanks for any information.
oldfred
Replies
NO!
> 80% depth of discharge always shortens battery cycle life, no matter what type rechargeable.
It is true that older NiCds have a memory effect (somewhat on newer cell structures) in that they would be needed to fully discharge every few years if charged properly during lifetime - gets to be a complex subject.
Anyway, when new, stick it on the recharger the very first sign of loss of torque and you will get lots more cycles out of them.
Thanks, Junkhound!
That's what I needed to know. I'd been clamping the trigger and waiting for them to run down. Your way is easier and I like easy.
oldfred
I know this goes against the experts but we have had great luck running them down. I think I have a picture of the thing we run them down with - it's made out of 2 inch PVC (heat gun reshaped with a battery shaped piece of wood) with 12 volt automobile "marker" bulb (I've never burned one of these out yet). I have three of these. We store the batts/charger in a briefcase and they can be put away in the drain mode.
I'm only talking about the old 9.6 standard NC battery. I have had a lot of experience with these - we had a "hazardous waste dump" last year and I threw away two five gallon buckets full of them. They seem to die like clockwork at 5 - 6 years. When we didn't run them completely down we seemed to only get 4 - 5 years. This may be pretty anecdotal, but our impression is you get longer life and better charge to keep all the cells in "sync".
I DON'T run down the new N-Hydride 12 and 14 volt batteries.